I agree with Chealsie508 in that a 100%, instant recall isn't likely possible. Sounds like the personality of your current one is a little less amicable than your last basenji.
Not being interested in food is a problem. I kind of feel your pain as my dog is more dog-oriented than food-oriented….so recall is all fine and good until a new dog comes along - then it's more of a challenge. Every dog has their weak spot though; squeaky toys? love of the chase? being petted? strange noises or objects?
What I found helpful (as I do walk with my dog off leash) is having three or four separate recalls each a different "level" if you will. In addition to an emergency 'get here now' recall. That way if one doesn't work you aren't out of tricks so to speak. The first one I do is more of a soft sound as in 'where are you, could you come here', the second one is a soft high pitched "c'mere" (like a playful request) the third one I have is forceful "Beo" and then an angry "ahh sound" - and the emergency recall is a loud,clear forcefully yelled "come". That one isn't optional. Hasn't failed me to date, but if he were to ignore that one back on the leash he'd go until we could reinforce it again.
Depending on the personality you might be able to run away or hide to coax them into coming back. Rewards with high-interest food is what I use, and it works, but obviously that won't work for you. Keeping your dog slightly hungry before practice might help with this. Being able to call a dog based purely on respect is all fine and dandy (and necessary I might add), but for an emergency instant recall you need something more convincing. Even k9 police dogs don't operate purely on 'respect'. I'll admit that I do bribe my dog, but it's been worth it.
Never tainting that particular recall is super important. Having extra recalls comes in handy to help with that. However, my dog is fairly Beta and we've been working on this for years to the point where it's just second nature at this point. Clicker training helped immensely in the beginning. Positive repetition is essential for them to react instantly when there really is a potential emergency; like being charged by a bull, or running with another dog towards a highway.
With that being said I doubt there are few basenjis out there that would be able to walk off leash perfectly while on the side of a busy highway. Location is probably the most important decision to be made. There are only a couple of really dangerous scenarios I can think of - cars and weather related issues (like falling through the ice) so if those can be avoided it helps. Along the way there will be screw ups, and it's best when it's not a screw up the one time where you actually need it.
Would be curious about the effectiveness of the electric collar.